CDKN2A and relapsing-remitting multiple sclerosis: Analysis of RUNX3, MLH1, IGF2, CDKN2A, SOCS1, NEUROG1, CACNA1G, and CRABP1 showed differential methylation of RUNX3, CDKN2A, SOCS1, and NEUROG1 in RRMS patients compared to controls; there were no differences between relapse and remission patients